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MedlinePlus is a service of the National Library of Medicine (NLM), the world's largest medical library, which is part of the National Institutes of Health (NIH). It was built as an online health information resource for patients and their families and friends.

MedlinePlus presents high-quality, easy to understand, relevant health and wellness information that is trusted.

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MedlinePlus at a Glance

  • Offers information on health topics, human genetics, medical tests, medications, dietary supplements, and healthy recipes.
  • Sourced from more than 1,600 selected organizations.
  • Provides 40,000 links to authoritative health information in English and 18,000 links to information in Spanish.
  • In 2018, 277 million users viewed MedlinePlus more than 700 million times.

Evaluating Health Information

Why do I need to evaluate health information?

Health information is easy to find. But finding reliable health information takes a little effort. Some of the health information you get from newspapers, magazines, books, TV, the Internet, and social media is up to date and trustworthy. But some is not. That's why it's important to evaluate health information for yourself.

But how can you tell the good from the bad? There are two key steps:

  • Ask questions before you trust what you read or hear.
  • Discuss the information you find with your health care provider before you rely on it. You may have found good information, but your provider can tell you whether it's good for you.
How can I evaluate health information on the Internet?

Asking a few questions will help you decide if you can trust a website. You can usually find most of the answers on the site's "About Us" page. If you can't find information about who runs the website, the site may not be trustworthy, and their health information may be unreliable. Some questions to ask are:

  • Who runs the site? Can you trust them to provide balanced, accurate information? Trustworthy sites provide a way to contact the owners with questions or feedback. In general, you'll find good health information on websites run by:
    • Federal government agencies.
    • Medical schools.
    • Large professional or nonprofit organizations. For example, the American College of Cardiology (a professional organization) and the American Heart Association (a nonprofit) and are both reliable sources of information on heart health.
  • What's the purpose of the site? Is it to:
    • Inform the public?
    • Sell products or services?
    • Promote the opinions of a person or group?
    A trustworthy website has one goal: To give you good information.
  • Who pays for the site?
    • If the site is funded by ads, they should be clearly marked as advertisements. Watch out for ads designed to look like neutral health information.
    • If a business pays for the site, the health information may favor that business and its products.
  • Is the health information high quality? Good health information doesn't promote one treatment over another. It gives you balanced facts based on research. So, beware of dramatic writing, promises of cures, and claims that sound too good to be true. Those could be signs of a health fraud scam. To evaluate the quality of a website's information, ask:
    • How is the information selected and reviewed to make sure it's accurate? Check the "About Us" page to see if the site has:
      • An editorial board of health experts
      • A content review process
      • A selection policy for content
      • Information about their writers' qualifications, which may be listed at the bottom of the articles
    • Where does the information come from? The content pages should have links or references to the sources of the information.
    • Is the information up to date? Content pages should include dates when the information was written, reviewed, or updated.
  • How does the website use your personal information? Look for a privacy policy section to see how your personal information will be used. Don't share information about yourself unless you're comfortable with any risks involved.

When you find a website that seems to be trustworthy, don't stop there. Look to see if other reliable sites have similar health information.

How can I evaluate health information on social media?

A social media post may come from someone you know, but that doesn't guarantee it's good information. Many of the questions you use to evaluate a website also work for social media too. Ask where the information comes from, why it exists, and if anyone is funding it.

If you're not sure whether the information you see on social media is trustworthy, don"t share it with others.

How can I evaluate health stories in the news?

Some news stories about medical research may not include all the facts you need to know. Ask these questions:

  • Does the story say whether the research involved people or animals?
  • If it was people, how many people were in the study and who were they?
  • How long was the study?
  • What type of study was it?
  • Who paid for the research?

If you learn a few tips for understanding medical research, you'll be able to decide if a news story may apply to your health. Then you can discuss the information with your provider.

How can I evaluate health information in books?

To evaluate health information in books, ask:

  • How old is the book?
  • Is the author an expert on the subject?
  • Does the book offer different points of view or just those of the author?
  • Has the book been reviewed by other experts?
  • Does the book list the sources of the content?

After you evaluate health information, talk with your provider before using it to make decisions that may affect your health.

NIH: National Library of Medicine